A team of researchers from the Purdue University in Indiana, US has developed a new manufacturing process to provide low-cost, sustainable option for food packaging.
Image: A nanocellulose-coated PET film. Photo: courtesy of Purdue University.
The new large-scale manufacturing process uses cellulose nanocrystals (CNCs) as advanced barrier coatings for food packaging.
The CNCs are said to be an alternative renewable raw material derived from abundant resources such as wood and plants.
Properties including nontoxicity, biodegradability, high specific strength, high thermal conductivity and optical transparency of the CNCs make them excellent components for advanced food packaging, the researchers said.
Purdue’s School of Materials Engineering professor Jeffrey Youngblood said: “The challenge for the food packaging industry is to create a recyclable and sustainable barrier material that is low-cost.
“Our innovation using CNC coatings is transparent, nontoxic and sustainable.”
Additionally, the manufacturing technique is scalable as the roll-to-roll process uses waterborne polymer systems, the researchers said.
Since the CNCs are highly crystalline and easily dispersed in water, they allow manufacturers to control the structure to eliminate free volume. As a result, manufacturers end up with only required properties for the barrier material.
Youngblood added: “Our unique process uses the power of natural nanotechnology and allows a much higher density and packing coating that reduces diffusion pathways and drastically improves oxygen, carbon dioxide and water vapor permeability.
“In essence, we get properties similar to common packaging such as ethylene-vinyl alcohol polymer, but with more sustainable results.”
Additionally, the new process offers enhanced optical, thermal and mechanical properties for food packaging manufacturers to ensure maximum freshness of the food when delivered to the grocery store.
Youngblood further said: “Technological advances such as this are important as there is a larger societal effort to improve sustainability.
“CNC offers this, along with transparency, nontoxicity and high barrier performance.”